Cross-compiling SableVM on a Gentoo System
------------------------------------------

This document describes how to cross-compile SableVM on a Gentoo system.

General Notes
-------------
Note: In the current portage version, stripping does not work for
      cross-compiled binaries as the native strip program is used.
      This will be fixed in the next portage version and there is a patch
      also available.
      Use FEATURES=nostrip is the simple solution.


0. Install a Gentoo system.

1. Install a cross-compiler toolchain

   See: http://dev.gentoo.org/~vapier/CROSS-COMPILE-HOWTO
   See: http://www.sable.mcgill.ca/~dbelan2/crossdev/crossdev-powerpc-i686.html

   Note I have to do these two modifications to build a cross-compiler
   toolchain on my systems:
   a) Build the kernel headers before gcc.
      Change "make prepare ..." for "make include/linux/version.h"
      in the headers ebuild.
   b) Add "--with-sysroot=/" to the gcc configure options in toolchain.eclass.

2. Cross-compile popt

ROOT=/usr/local/cross-root \
USE=-nls
CHOST=powerpc-unknown-linux-gnu \
CFLAGS="-O2 -g" \
emerge -av --nodeps popt

3. Cross-compile libffi

ROOT=/usr/local/cross-root \
USE=-nls \
CHOST=powerpc-unknown-linux-gnu \
CFLAGS="-O2 -g" \
emerge -av --nodeps libffi

4. Cross-compile libtool (for libltdl)

ROOT=/usr/local/cross-root \
USE=-nls \
CHOST=powerpc-unknown-linux-gnu \
CFLAGS="-O2 -g" \
emerge -av --nodeps libtool

5. Cross-compile zlib

Apply this patch to the zlib ebuild:

--- /usr/portage/sys-libs/zlib/zlib-1.2.2.ebuild        2004-12-06 01:39:29.000000000 -0500
+++ /usr/local/portage/sys-libs/zlib/zlib-1.2.2.ebuild  2004-12-16 23:29:41.000000000 -0500
@@ -68,5 +68,5 @@
        dosym libz.so.${PV} /$(get_libdir)/libz.so
        dosym libz.so.${PV} /$(get_libdir)/libz.so.1
        # with an extra symlink at /usr/lib
-       dosym /$(get_libdir)/libz.so.${PV} /usr/$(get_libdir)/libz.so
+       dosym ${ROOT}$(get_libdir)/libz.so.${PV} /usr/$(get_libdir)/libz.so
 }


ROOT=/usr/local/cross-root \
USE=-nls \
CHOST=powerpc-unknown-linux-gnu \
CFLAGS="-O2 -g" \
emerge -av --nodeps zlib

6. (Optionnally) Cross-compile all required libs for gtk.

7. Cross-compile SableVM

Support in ebuild >=dev-java/sablevm-svn-20041216-r1.
Available here:
http://www.sable.mcgill.ca/~dbelan2/ebuilds/dev-java/sablevm-svn/

ROOT=/usr/local/cross-root \
CHOST=i686-pc-linux-gnu \
CFLAGS="-O2" \
LDFLAGS="-L/usr/local/cross-root/lib \
  -L/usr/local/cross-root/usr/lib \
  -L/usr/local/cross-root/usr/lib/libffi" \
CPPFLAGS="-I/usr/local/cross-root/usr/include \
  -I/usr/local/cross-root/usr/include/libffi" \
emerge -av --nodeps sablevm-svn